"Whilst we all want our customers to stay, we believe there needs to be a proper and seamless process to allow customers to move, should they choose to do so," Richard Sweet, chair of the working group behind the code, told the BBC.
The system depends on a "migration authorisation code" (MAC), which will be given on request to an account holder by his existing provider. The account holder then gives the code to the provider to which he wishes to transfer. Only then can the new service be connected.
The losing service provider may only withhold the authorisation code if the account holder is dead, if it cannot verify the identity of the person who made the request, or if the contract has already come to an end. It cannot withhold a request for a MAC for debt enforcement or contractual purposes.
However, an account holder is still bound by the terms of his original contract with his first service provider – and may still have to pay an early cancellation fee, or complete the payments on that contract.
The code of practice only covers broadband services delivered by certain BT lines. It does not extend to cable services. Nor does it cover all broadband service providers.
Companies that have signed up to the code so far include AOL, BT, Easynet, Telefonica UK, Virgin.net and Wanadoo. All signatories have agreed to be in a position to comply with the new system by 16th August.